OPERATOR INTERACTION DURING AN SFC PHASE
An OPD can be applied during an SFC phase. The simplest operator interaction could be to ask the operator to acknowledge an OPD message before entering the next step of the phase. Another example is to ask the operator to select between two storage tanks. Each one of the cases above can also require one or several electronic signatures.
OPERATOR INTERACTION BETWEEN TWO SFC PHASES
An OPD can also be applied for operator interactions on the batch level, between two separate SFC phases. The operator could be asked to choose between different equipments, which require separate unit allocations.
OPERATOR INTERACTION FOR EVENT BASED ACTIONS
An OPD can be used for event based actions. The operator could be asked to acknowledge an OPD message before opening a valve or closing a pump. Or changing some parameters or alarm limits.
ELECTRONIC SIGNATURES IN APL
OPD can be used to add comments and electronic signatures during APL operational commands e.g. mode switching or setpoint adjustment.
OPD can be also used to scan barcodes. Why not combine a barcode and an electronic signature in one single operator dialog.